Cosmetics company L'Oreal has been accused of "whitening" singer Beyoncé Knowles' skin colour in a series of press ads in women's magazines in the US.

The ads, for L'Oreal Paris' Feria hair colour product, feature in the September editions of Elle, Allure and Essence magazines in the US.

In the ads the 26-year-old star, who is married to rapper Jay Z, appears to be much whiter than typical pictures of the singer-cum-actress.

There has been a backlash in the US over the images. The New York post said that the "digital lightening" made her "virtually unrecognisable".

Gossip website TMZ described the Beyoncé images as "bleached out" and "Photoshopped", launching an online poll to ask if the whitening was "a slap to blacks?".

However, L'Oreal maintained there has been no lightening of the singer's complexion in the ads.

"We highly value our relationship with Ms Knowles. It is categorically untrue that L'Oreal Paris altered Ms Knowles' features or skin tone in the campaign for Feria hair color," the company said in a statement.

Knowles has worked with the cosmetics company since 2001.

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